waitid.c

Glibc 2.3.2源代码(解压后有100多M)

/* Pseudo implementation of waitid.
   Copyright (C) 1997, 1998, 2000, 2002 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Zack Weinberg <[e-mail]>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <errno.h>
#include <signal.h>
#define __need_NULL
#include <stddef.h>
#include <sys/wait.h>
#include <sys/types.h>

#include <assert.h>

extern pid_t kwaitpid (int *stat_loc, pid_t pid, int options,
		       struct rusage *ru_loc, siginfo_t *infop);

int
__waitid (idtype, id, infop, options)
     idtype_t idtype;
     id_t id;
     siginfo_t *infop;
     int options;
{
  pid_t pid, child;
  int status;

  switch (idtype)
    {
    case P_PID:
      if(id <= 0)
	goto invalid;
      pid = (pid_t) id;
      break;
    case P_PGID:
      if (id < 0 || id == 1)
	goto invalid;
      pid = (pid_t) -id;
      break;
    case P_ALL:
      pid = -1;
      break;
    default:
    invalid:
      __set_errno (EINVAL);
      return -1;
    }

  /* Technically we're supposed to return EFAULT if infop is bogus,
     but that would involve mucking with signals, which is
     too much hassle.  User will have to deal with SIGSEGV/SIGBUS.
     We just check for a null pointer. */

  if (infop == NULL)
    {
      __set_errno (EFAULT);
      return -1;
    }

  child = kwaitpid (&status, pid, options, NULL, infop);

  if (child == -1)
    /* `waitpid' set `errno' for us.  */
    return -1;

  return 0;
}
weak_alias (__waitid, waitid)